Self-propelled water skimmers



6, 1969 E. s. DAWSON SELF-PHOPELLED WATER SKIMMERS Filed Dec.

mm Nmqw mm @Q n HU R/l/EyS United States Patent 3,463,116 SELF-PROPELLED WATER SKiMMERS Edward S. Dawson, Edmonton, Alberta, Canada, assignor to Surf Skimmer Ltd., Edmonton, Alberta, Canada Filed Dec. 5, 1967, Ser. No. 688,214 Claims priority, application Canada, Nov. 9, 1967,

Int. Cl. A63h /08, 15/00 US. Cl. 11570 6 Claims ABSTRACT OF THE DISCLOSURE A self-propelled water skimmer includes a body with the general configuration of a surfboard and an impeller mounted in a water passage in the body of the skimmer for rotation about a vertical axis. The impeller is driven by a prime mover secured to the rear portion of the body and has a vertical output shaft projecting into the water passage, the impeller being secured to the output shaft.

This invention relates to self-propelled water skimmers. Such skimmers are sometimes referred to as motorized surfboards.

In some known skimmers, an engine-driven impeller is located in a water passage in the rear portion of the skimmer. In operation, the impeller draws in water through an inlet to the passage and expels the water as a jet through an outlet from the passage to propel the skimmer forwardly. This type of propulsion is preferable to the use of an externally-mounted propeller since a propeller may injure someone in the water. An impeller cannot injure anyone in this way since it is located within the body of the skimmer.

It is an object of this invention to provide an improved water skimmer of the type using water jet propulsion.

It is a further object to provide a water skimmer of this type with a relatively compact propulsion assembly.

According to the invention, the engine or other prime mover is mounted so as to provide a substantially vertical output shaft which projects into the water passage, the impeller being mounted on the shaft. The engine or other prime mover may be mounted on a member which is substantially level with the deck of the skimmer, thereby reducing the likelihood of flooding of the engine or other prime mover.

The water skimmer may be provided with a rudder which is responsive to the force exerted by the water jet in such a manner that, when the prime mover is at idling speed, the rudder steers the skimmer in a circular path and, when the prime mover is substantially above idling speed, the rudder is moved by the water jet to a straight ahead position.

The speed of the prime mover may be controlled by a squeezable handgrip connected to the prime mover by a Bowden cable arrangement, the handgrip containing a series of links so arranged that squeezing of the handgrip causes relative movement between the outer and inner parts of the Bowden cable assembly to increase the speed of the prime mover.

The arrangement may be such that, if an operator falls off the skimmer and loses grip of the handgrip, the speed of the prime mover is automatically reduced to idling speed. When the skimmer has a rudder as mentioned above, the skimmer will then be steered in a circular path, thus making it easy for the operator to reboard the skimmer.

One embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, of which:

FIG. 1 is a perspective view of a water-skimmer,

3 ,463,1 l6 Patented Aug. 26, 1969 FIG. 2 is a fragmentary plan view with certain parts removed to show the water passage,

FIG. 3 is a longitudinal sectional view taken along the line 33 of FIG. 2,

FIG. 4 is an exploded perspective view of the impeller housing,

FIG. 5 is a fragmentary side view of the rudder assembly, and

FIG. 6 is a longitudinal sectional view of the hand-grip which actuates the throttle.

Referring to the drawings, a water-skimmer has a body 1 which in general configuration resembles a surf-board. The body 1 has a raised portion adjacent its rear end, the rear end being formed by a stern 3 which is substantially vertical and extends the full width of the body 1 at right angles to the longitudinal axis of the body. The opposite sides 4 of the body I extend in a parallel manner from the rear end to a near mid-length position 5, and then curve towards one another to merge into a partspherical bow 6. The sides 4 are gently radiused to merge with the underside '7 and the deck 8. From the near midlength position 5, the underside 7 extends forwardly and upwardly at an angle A to the rear horizontal portion of the underside so as to merge with the deck 8 at the how 6. Near the how 6 are two laterally-spaced rings 9 to which handlines 11 are attached. The body 1 has a buoyant foam core 12 with a fibre glass skin 13.

The raised portion 2 of the body 1 forms an engine housing and has a hinged cover 14 given access to an engine compartment 15. The engine 16 is an internal combustion engine secured to the floor of the compartment 15 with its crankshaft 18 vertical and the longitudinal axis of its cylinder 19 horizontal. The crankshaft 18 extends downwardly through the floor 17 into a water passage 21, and a centrifugal impeller 22 in the water passage 21 is mounted on the crankshaft 18 so that the engine 16 is above the water level.

The water passage 21 includes an intake duct 23 which has an inlet 24 in the underside 7 of the body 1 and extends upwardly and rearwardly from the inlet 24 to the medial area of the lower side of the impeller 22. The intake duct 23 communicates at its upper end with a pump chamber 25 in which the impeller 22 is eccentrically mounted. A discharge duct 26 extends from the pump chamber 25 to an outlet 27 at the stern 3. FIG. 4 shows two impeller housing members 28 which form the pump chamber 25 and the initial portion of the discharge duct 26. The members 28 form a bafiie 29 created by intersecting curvatures at the junction of the pump chamber 25 and the discharge duct 26 to help arrest return eddies and build up discharge pressure. In the arrangement shown in FIG. 2, the impeller 22 (shown in dotted outline) rotates in a clockwise direction.

The rear portion of the discharge duct 26 is an enlarged portion 31 which forms a rearwardly-facing shoulder 32 at its junction with the initial portion of the discharge duct 26. A rudder 33 is pivotally mounted for movement about a vertical axis on one side of the discharge duct 26 at a laterally-inner edge of the shoulder 32. A spring 34 urges the rudder 33 angularly towards the longitudinal axis of the discharge duct 26, the strength of the spring 34 being such as to achieve a desired effect which will be described later.

The engine 16 has a throttle lever 35 which is remotely actuated by a handgrip 36 connected to the lever 35 by a Bowden cable assembly 37. As shown in FIG. 6, the handgrip 36 has a hollow flexible housing 38 secured to the outer casing 39 of the Bowden cable assembly 37. Within the housing 38, a first pair of links 41 are pivotally connected at one end to a collar 42 rigidly secured to the outer casing 39 of the Bowden cable assembly 37. A second pair of links 43 are pivotally connected at one end by pivotal connections 44 to the opposite ends of links 41 and are pivotally connected at the other end to the inner wire 45 of the Bowden cable assembly 37. The pivotal connections 44 engage metal guides 45a mounted in the housing 38.

The throttle lever 35 is resiliently biased by a spring (not shown) to the position shown in FIG. 3 at which the engine 16 idles. By squeezing the handgrip 36, the links 41, 43 are displaced from the position shown in full outline in FIG. 6 towards the position shown in dotted outline, with the pivotal connections 44 being guided by guides 45a, to cause relative movement between the inner wire 45 and outer casing 39 of the Bowden cable assembly 37 and thereby actuate the throttle lever 35 to increase engine speed. The carburetor 46 of the engine 16 is connected by a fuel pipe 47 to a fuel tank 48 embedded in the body 1.

An electrical switch 49 is mounted in the housing 38 of the handgrip 36 and is connected by wires 51 to an electrical generator (not shown) driven by the engine 16 and to a siren 52. The siren 52 can be operated by pressing the switch 49. The generator is also connected by wires 53 to a headlight 54 attached to the deck 8 near the bow 6 by a vacuum cup 55 and to sidelights 56 at opposite side of the raised portion 2. Switches (not shown) are provided for controlling operation of the headlight 54 and sidelights 56. The engine compartment contains a storage compartment 57 for storage of the headlight 54 when not in use.

To operate the skimmer, the operator starts the engine 16 which then idles at such a speed that very little propolling force is applied by the impeller 22 to the Water jet. When the force exerted by the water jet on the rudder 33 is less than the amount produced by an engine speed just above idling, the spring 34 forces the rudder 33 to move angularly towards the center of the discharge duct 26 so that skimmer is steered in a circular path. Thus any forward movement of the skimmer while the engine is idling is in a circular path.

After starting the engine, the operator sits, kneels or stands on the deck 8 holding the handlines 11 and the handgrip 36. By squeezing the handgrip 36, the throttle lever 35 is actuated to increase engine speed and consequently the speed of the water jet discharged from the outlet 27. The rudder 33 is moved to the straight ahead position by the more powerful water jet which overcomes the spring 34, and the skimmer moves forwardly in a substantially straight line. During such movement, the operator can sound the siren 52 if necessary by pressing the switch 49 on the handgrip 36.

If the operator falls off the skimmer while travelling at speed and loses grip of the handgrip 36, the throttle lever 35 is returned to the idling position by its spring (not shown). The engine speed therefore reduces to idling speed and consequently the rudder 33 is returned to the circling position by the spring 34. Thus the skimmer travels at a slow speed in a circular path, making it easy for the operator to reboard the skimmer.

It will be seen that the invention provides a water skimmer with a compact propulsion unit and this enables the water skimmer to be constructed so as to have a relatively high buoyancy, to be self-righting, and to be capable of relatively high speeds, in addition to having the features already mentioned.

I claim:

1. A self-propelled water skimmer including a body with the general configuration of a surfboard, the body having a raised rear portion containing a prime mover compartment having a fixed floor, the body also having a water passage passing below the floor of the prime mover compartment from an inlet to an outlet, a prime mover located in said compartment and fixedly secured to said floor, the prime mover having a substantially vertical output shaft projecting downwardly through said floor into the water passage, and an impeller located in the water passage and mounted on the shaft for rotation by the prime mover about a substantially vertically axis to discharge a water jet from the passage outlet to propel the skimmer.

2. A water skimmer according to claim 1 wherein the body has a deck extending forward from the raised portion and the floor of the prime mover compartment is substantially level with the deck.

3. A water skimmer according to claim 1, wherein the prime mover is an internal combustion engine with a vertical crankshaft and a cylinder with a horizontal longitudinal axis.

4. A water skimmer according to claim 1, including a rudder mounted adjacent the outlet of the water passage for angular movement about a substantially vertical axis, and resilient means urging the rudder towards a position in which the skimmer is steered in a circular path, the strength of the resilient means being such that, when the prime mover is at idling speeds, the resilient means maintains the rudder in the circular path position and, when the prime mover is substantially above idling speed, the force exerted by the water jet on the rudder moves the rudder to a straight ahead position.

5. A water skimmer according to claim 1, including a squeezable handgrip connected to the prime mover by a Bowden cable assembly for remotely controlling the speed of the prime mover, said Bowden cable assembly having relatively movable inner and outer parts, said handgrip including a housing secured to the outer part and two pairs of links, one end of a first link in each pair being pivotally connected to the outer part, the other ends of said first links being pivotally connected to one end of the second link of the respective pair, the other ends of said second links being pivotally connected to the inner part of the Bowden cable assembly, and said first links diverging from the outer part to their pivotal connections with the second links and said second links converging from the last mentioned pivotal connections to the inner part, whereby squeezing of the handgrip causes relative movement of the links and consequent relative movement of the Bowden cable parts to increase the speed of the prime mover.

6. A water skimmer according to claim 1, including a rudder mounted adjacent the outlet of the water passage for angular movement about a substantially vertical axis, resilient means urging the rudder towards a position in which the skimmer is steered in a circular path, the strength of the resilient means being such that, when the prime mover is at idling speeds, the resilient means maintains the rudder in the circular path position and, when the prime mover is substantially above idling speed, the force exerted by the water jet on the rudder moves the rudder to the straight ahead position, a manually operable handgrip connected to the prime mover by a flexible cable assembly for remotely controlling the speed of the prime mover, and means for causing the prime mover to operate at idling speed in the absence of manual operation of the handgrip.

References Cited UNITED STATES PATENTS 3,046,697 7/1962 Pullen -16 X 3,224,408 12/ 1965 Sfredda 115-12 3,324,822 6/ 1967 Carter.

FOREIGN PATENTS 1,141,185 3/ 1957 France.

TRYGVE M. BLIX, Primary Examiner 

